Please activate JavaScript!
Please install Adobe Flash Player, click here for download
ePaper created 2016-06-09, 15:16:05 | version 1.38.0
Journal of Oral Science & Rehabilitation 22 Volume 2 | Issue 2/2016 T h r e e - y e a r r e s u l t s o f A l l - o n - 4 i n d a i l y p r a c t i c e right canine.The implantwas leftto healforfour months accordingto a conventionalloading pro- tocol. The othertwo complications were periim- plantitis, consisting of a mean mesiodistal peri- implant bone loss of2.6 and 2.8mm, reported at the one-year follow-up examination. The first caseofperiimplantitisdevelopedarounda15mm longimplantinposition35,placedusingconven- tional freehand surgery in a healed site. The sec- ondcasedevelopedarounda13mmlongimplant in position 32, placed using guided surgery in a healed site and immediately loaded. No other technical or biological complications occurred during the entire follow-up period. After an initial mean marginal bone loss of 1.16±0.40mm(1.06mm;95%CI:0.92–1.20),all of the implants lost a mean of 0.21 ± 0.11 mm (0.20mm; 95% CI: 0.16–0.24) betweenthe one- and two-year follow-ups, and 0.16 ± 0.07 mm (0.15mm; 95% CI: 0.13–0.17) between the two- and three-year follow-ups. At the three-year follow-up, the mean marginal bone loss was 1.52±0.41mm(1.42mm;95%CI:1.27–1.57).The radiographic data are shown in Table 2. All of the patients were fully satisfied with thefunctionandestheticsoftheirdefinitivepros- theses, and all of the patients declared that they would undergo the same treatment again. M a x i l l a v e r s u s m a n d i b l e Twelvepatientsweretreatedinthemaxilla,while 18 patients were treated in the mandible. There were no statistically significant differences be- tween centers for the number of patients who hadfailed implants (1/12vs. 0/18; risk ratio = NA; p=0.399) or complications (3/12 vs. 8/18; risk ratio=0.5625; 95% CI: 0.19–1.70; p=0.442). At the three-yearfollow-up examination, the mean marginalbonelosswas1.49±0.34mm(1.42mm; 95% CI: 1.23–1.61) in the maxilla versus 1.54±0.46mm (1.38mm; 95% CI: 1.17–1.59) in the mandible (p=0.756). The radiographic data are shown in Table 3. G u i d e d v e r s u s c o n v e n t i o n a l f r e e h a n d s u r g e r y Fifteenpatientsweretreatedusingcomputer-as- sisted template-based surgery and 15 with con- ventional freehand surgery. There were no sta- tisticallysignificant differences between centers for the number of patients who had failed implants (1/15vs. 0/15; risk ratio=NA;p=0.999) orcomplications(4/15vs.7/15;riskratio=0.5714; 95% CI: 0.21–1.55; p = 0.449). At the three-year follow-up examination, the mean marginal bone loss was 1.48 ± 0.47 mm (1.33 mm; 95% CI: 1.09–1.57) in the guided surgery group versus 1.55±0.34mm (1.46mm; 95% CI: 1.29–1.63) in the conventional freehand surgery group (p = 0.365). The radiographic data are shown in Table 3. Discussion The present study reported data on 30 im- plant-supportedrestorationsdeliveredaccording to the All-on-4 protocol and followed for at least three years after implant placement. Because it was designed as a single-cohort prospective study,themainlimitationofthepresentresearch wasthelackofacontrolgroupandthesmallsam- ple size. Another limitation of the present study was the variability within the cohort of patients. In the present study, the three-year implant (99.2%) and prosthesis success rates (100.0%), as well as the mean bone loss of 1.52±0.41 mm, indicatethattheAll-on-4treatment concept is a promisingtreatment modality. Furthermore,the results of this prospective observational study are consistent with other studies investigating the same topic. A recent systematic review by Patzelt et al., which included 4,804 implants, demonstrated a mean cumulative implant and prosthesis survi- val rate at three years of 99.0 ± 1.0% and 99.9± 0.3%, respectively.20 The mean bone loss at three years amounted to 1.3±0.4 mm. Howe- ver, 12 out of the 13 included studies were consi- dered to be highly biased. Most of the studies included (69%) in the systematic review derived fromalimitednumberofinvestigatorsinItalyand Portugal, which may limit the generalizability of thefindings,andonly31%ofthestudiesreported a completed follow-up period of three years. Malo et al. retrospectively reported a cumu- lative patient-related success rate of 93.8% up to ten years of follow-up in the mandible and a prosthesis survival rate of 99.2%.18 In the maxil- la, a five-year survival rate of93%was reported, and the survival rate of the prostheses was 100%.19 The mean marginal bone loss was 1.52 ±0.30 mm afterthree years. Similar results were reported by Browaeys et al., who highligh- ted unacceptable ongoing bone loss in 49.2% of the patients.32 Balshi et al. retrospectivelyanalyzedthe out- comes of 200 arches (800 implants) treated